1. Field of the Invention
Embodiments of the invention relate to a device and a method for handling electromagnetic fields, specifically, such fields as occur in devices for magnetic resonance tomography. (“MRT” or “MRI” stand for magnetic resonance tomography and magnetic resonance imaging respectively, wherein these two acronyms are used interchangeably herein).
2. Description of the Related Art
Although MRI examinations are becoming increasingly important in diagnostic medicine, a certain fraction of patients is contraindicated for MRI examinations. This type of contraindication can be caused by an at least partially implanted medical device (hereafter also: implant or IMD).
In order to be able to effect MRI examinations despite this fact, various approaches are known that relate either to the implementation of the MRI examination or to the implantable medical device.
US 2005/0070787 A1 thus discloses an approach whereby communication is established between an MRI device and an implant, thereby enabling the implant with information from the MRI device to deactivate one or more components of the implant during the delivery of RF pulses by the MRI device. To this end, as is described, it is necessary for communication to take place between implant and MRI device, which action requires a common communications protocol and compatible communications capabilities on each side. Aside from the thus necessary compatibility requirements and additionally necessary communications units, specifically on the side of the MRI devices, a further disadvantage is the long transitional period involved until a significant fraction of the MRI devices allow for safe MRI examinations of implant patients to occur.
A similar approach is pursued by EP 2 062 525. This describes an RFID system on electrode leads belonging to an implant that allows for a flow of information from the RFID tag to an MRI device. This system thus requires MRI devices that have a unit to read the RFID tags. Aside from the thus necessary compatibility requirements and additionally necessary RFID units, specifically on the side of the MRI devices, a further disadvantage is the long transitional period involved until a significant fraction of the MRI devices allow for safe MRI examinations of implant patients to occur through existing RFID read units.
In addition, both prior-art systems require the given MRI device to be equipped with updated information about the specific implant.